This invention relates to heating systems in general and more particularly to an improved auxiliary hot water boiler and heat exchange system adapted for interconnection with a solar heat absorber and the heating plant and hot water heater of a conventional home.
Generally speaking, such systems are disclosed in several prior art patents. U.S. Pat. No. 4,034,738 issued July 12, 1977 to E. M. Barber, Jr. discloses a solar heating system including a main water storage tank heated from a solar heat absorber through a closed circuit fluid system and a heat exchanger. An additional heat exchanger in the main tank supplies heated water to a conventional, domestic hot water heater. Yet another heat exchanger in the main tank provides a source of heat for a domestic heating system through a closed loop. Fluid is pumped through the loop and the pump is thermostat controlled. Alternatively, this last mentioned heat exchanger may be eliminated and hot water in the main tank may be pumped directly to the domestic heating system.
A disclosure of a hot water heater, wherein both firebox and the flue thereof are surrounded by water to be heated, appears in U.S. Pat. No. 2,704,188 issued Mar. 15, 1955 to R. L. Bergueau. An additional disclosure of using solar energy to heat the water of a conventional hot water heater appears in U.S. Pat. No. 4,126,122 issued Nov. 21, 1978 to T. D. Bross. U.S. Pat. No. 4,050,626, issued Sept. 27, 1977 to T. Y. Awalt Jr., shows a solar water heater with a direct combustion assist for heating the water.
A tank having dual water compartments and a heat exchanger to service a domestic hot water system, an auxiliary heater, a solar heat absorber and a heat exchanger providing hot water to a heating coil or heat pump is set forth in U.S. Pat. No. 4,119,086 issued Oct. 10, 1978 to N. E. Brussels. Other relevant disclosures of solar heating systems designed for domestic use appear in U.S. Pat. No.'s 2,689,090 issued Sept. 14, 1954 to G. D. Wetherbee et al and 4,143,642 issued Mar. 13, 1979 to A. A. Beanlieu.
While it is readily apparent in that major components of the instant invention are disclosed in one or more of the prior art patents above enumerated, the relatively compact subassembly system herein detailed and claimed is not disclosed by these patents nor is the overall system taught thereby. More specifically, the prior art does not anticipate an auxiliary hot water boiler and heat exchanger system including a main water tank having up to three heat exchangers therein, the first heat exchanger receiving heat from a solar heat exchanger, the second heat exchanger providing preheated water for a domestic hot water heater, and the third heat exchanger providing hot water for an additional use or uses (e.g., for heating swimming pool water), the third heat exchanger being supplemented by an additional boiler having a flue directed through the main tank to further heat water therein, water in the main tank being pumped to a domestic, closed loop hot water system; additionally, the main tank has one or more fireboxes directly incorporated therein, the flues thereof being surrounded by water in the main tank to further heat the main tank water supply.